In the arcane language of House and Senate appropriators, endorsed by veto-proof majorities in both chambers, lawmakers said Trump could have no more than $1.375 billion to build 55 new miles of steel fencing and specifically cited the risk to law enforcement in banning him from constructing solid walls.

It was a resounding and explicit rejection of the idea that there is a national emergency requiring billions of dollars to build a border wall. And that judgment was rendered at a time when Trump has been making a very public case — in speeches, interviews and tweets — that there is a "humanitarian and security crisis" and after he shut down the government for 35 days to make his point.

This is not a case in which an act of God or war struck when Congress was dormant; lawmakers reacted — just not in the way the president had hoped.

Put simply, Congress heard Trump's plea for emergency funding and used its primary authority under the Constitution — the power of the purse — to say no.

That's not an answer Trump likes to hear. So he's not taking it.

Instead, he is planning to announce Friday morning that he will declare a national emergency and draw $8 billion from the just-passed bill and other existing federal accounts to build the wall anyway, according to an administration official. Lawsuits will ensue, and the courts will have to decide whether and how to intervene in a power struggle between the other two branches.

Whatever the case at the border, there's now a clear constitutional crisis that will bolster the power of either Congress or the president.

"I don't want to see him do that, but it is sad that he is in the position of even having to do that and he would not need to do that had Congress simply done their job and funded the government and funded the wall," Rep. Rob Bishop, R-Utah, said before the president's decision had been confirmed. "Blame Congress."

Rep. Donna Shalala, D-Fla., a former secretary of Health and Human Services under President Bill Clinton, said it would be improper for Trump to take money intended for other purposes and shift it to building a wall.

"That's why there's going to be a legal challenge," she said. "I hope he doesn't do that."

Many Republicans, particularly establishment conservatives, have said in recent weeks that it's a bad idea for Trump to use executive powers to circumvent Congress. They envision a Democratic president tapping emergency powers and federal accounts to address liberal wish lists in the future.

But on Thursday, it wasn't that hard to find Republicans on Capitol Hill who were fully behind Trump.

"If we have a national emergency issue, which we have — we have a crisis going on on the border — then I support his ability to do what he needs to at that point," said Rep. Markwayne Mullin, R-Okla.

Democrats said there was no crisis, other than the political box Trump built for himself by promising his base that he would build the wall in the first place.

"This is a fake emergency," said Rep. Joaquin Castro, D-Texas. "In the past, presidents have called national emergencies over national security issues or disasters."

Castro said that he is prepared to introduce a measure that would terminate Trump's emergency declaration, which could get a vote in the House but is unlikely to see floor action in the Republican-controlled Senate.

In order to stop the process he's launching today, the president would have to sign a termination measure, or it would have to get a two-thirds majority over his veto.

"I don't believe he would have the support in the Senate — if they're required to vote," Castro said.

Sen. John Cornyn, R-Texas, suggested the same in criticizing the impending move by Trump.

"I think it's a dangerous step," he said. "One, because of the precedent it sets. Two, because the president is going to get sued and it won't succeed in accomplishing his goal, and three, because I think [Speaker Nancy] Pelosi will then introduce a resolution which will pass the House, then come over here and divide Republicans. So to me, it strikes me as not a good strategy."

In theory, Congress could have gone further to stop Trump from building a wall. The new bill could have included a so-called 'none-of-the-funds' provision prohibiting him from using any federal money to build a barrier along the border. But a provision like that would surely have drawn a veto — if it didn't sink the bill in the Senate — and possibly forced another government shutdown.

Given its strong desire to avoid that, Congress spoke as forcefully as it could to pre-empt Trump's emergency declaration.